The Dental cosmos . This of course presupposesthat the upper and lower teeth havebeen brought to the desired relative po-sitions, and that the cusps of the buccalteeth perfectly interdigitate, though per-haps not in typically normal are, however, a number of impor-tant supplements to this appliance whichwill be demanded for the retention ofextensive movements. RETENTION OF LATERAL EXPANSIONS. If one arch has been laterally expandedto the desired occlusion with the normalopposing arch which has not been moved,the simple six-band labial fixture shownin Fi#. 1 will usually retain
The Dental cosmos . This of course presupposesthat the upper and lower teeth havebeen brought to the desired relative po-sitions, and that the cusps of the buccalteeth perfectly interdigitate, though per-haps not in typically normal are, however, a number of impor-tant supplements to this appliance whichwill be demanded for the retention ofextensive movements. RETENTION OF LATERAL EXPANSIONS. If one arch has been laterally expandedto the desired occlusion with the normalopposing arch which has not been moved,the simple six-band labial fixture shownin Fi#. 1 will usually retain the expan-sion and any changed curve or mal-align-ment of the labial arch. But if the op-eration has been performed without dueregard to the forces of occlusion, and theopposing arch has been allowed to remainlaterally contracted, the stability of theseunmoved teeth will surely drive the ex-panded teeth back to their former posi-tion. This force of occlusion will fre-quently be sufficient to bend or displace Fig. any labial retainer that is not of unusualproportions, and will finally complete thefailure of the operation after the retaineris removed. When both arches havebeen laterally expanded—as they shouldbe in the last-named condition—and ifthe lower expansion be supported with aclasp-metal bow Xo. 16 or 14 soldered tothe lingual face of the six-band labialretainer as shown in Fig. 3, the forcesof occlusion in connection with the regu-lar upper labial retainer shown in Fig. 8will usually be sufficient to hold botharches in position. With certain occlusions it may befound expedient to attach the lingualbow to the upper arch instead of to thelower, and in some instances to both. Thelength of the arms and the size of thewire for the lingual bow will be governedby the demands of the case. If the distalarea has been much expanded, with a de-mand that the arms extend to the molars, CASE. SUPPLEMENTARY RETAINING FORCES, ETC. 25 they should be supported by thin lingualtubes
Size: 1870px × 1337px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthor, bookcentury1900, bookdecade1900, booksubjectdentistry
